Improvement in step-ladders



S. WRIGHT.

Step-Ladders. Nc .138,977. Pamted ma mmms WJYNEEEES, )Sr 3 INVENUR.

ad/QM AM PHOTD-UTHOGIMPHIC C0 N. m OSBORNEPROCESS UNITED STATES PATENTOFFICE.

SAMUEL WRIGHT, OF HILLSBOROUGH, MISSOURI.

IMPROVEMENT IN STEP-LADDERS.

Specification forming part of Letters Patent No. 138,977, dated May 13,1873; application filed March 11, 1873.

To all whom it may concern:

Be it known that I, S. WRIGHT, of Hillsborough, county of Jefferson andState of Missouri, have invented certain new and useful Improvements inStep-Ladders, of which the following is a specification:

The nature of my invention relates to an improvement in step-ladders;and consists in attaching the braces or legs to the brackets by means ofsocket-joints, allowing each leg a free and independent movement, sothat they can adjust themselves to any inequality of the earth, as willbe more fully set forth hereafter.

Figure 1 represents a side elevation of my ladder. Fig. 2 is a rear viewof the same.

a represents an ordinary step-ladder, provided with the brackets c, towhich the legs 0 are attached by means of the socket-joints i.

Heretofore the legs have been merelyhinged to the ladder, so as to swingback and forth, and have been rigidly braced together; and as long asthe ladder is used upon perfectly flat even surfaces, they answer everypurpose; but as soon as the ladder is moved upon uneven ground, the legsbeing braced rigidly together, only one will touch the ground; or, ifboth legs rest upon the ground, then only one side of the ladder willtouch it, making it unsafe to use it. In order to overcome thisdifficulty, I secure the legs through the brackets to the cross-bar Z,either by the socket-joint i, as shown, or by a ball and socket, or anyother suitable joint, which will allow each leg a limited, free, andindependent movement, so that they will readily adjust themselves to anyinequality of surface, as shown in Fig. 2. Then it is only necessary toplace the ladder firmly on the ground, and the legs can be arranged tobrace it as firmly as though the surface was perfectly fiat and even.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

A step-ladder, having its legs or braces secured to it by means ofjoints, so as to allow each leg a limited, free, and independentmovement, substantially as set forth.

In testimony that I claim the foregoing as 7 my invention, I hereuntoaffix my signature this 5th day of March, 1873.

SAMUEL WRIGHT.

Witnesses:

T. N. DONNELL, W. MITCHELL.

